Illustration of the early solar disk, with an inset image of a blue hibonite crystal, one of the first minerals to form in the Solar System. Image credit: Field Museum, University of Chicago, NASA, ESA, and E. Feild (STScl).Our Sun’s beginnings are a mystery. It burst into being 4.6 billion years ago, about 50 million years before the Earth formed. Since the Sun is older than the Earth, it’s hard to find physical objects that were around in the Sun’s earliest days—materials that bear chemical records of the early Sun. But in a new study in Nature Astronomy, ancient blue crystals trapped in meteorites reveal what the early Sun was like. And apparently, it had a pretty rowdy start.“The Sun was very active in its early life—it had more eruptions and gave off a more intense stream of charged particles. I think of my son, he’s three, he’s very active too,” says Philipp Heck, a curator at the Field Museum, professor at the University of Chicago, United States. “Almost nothing in the Solar System is old enough to really confirm the early Sun’s activity, but these minerals from meteorites in the Field Museum’s collections are old enough. They’re ...